Annular Gear
A gear wheel in which the teeth are on the inside of an annulus or ring, while its pinion works within its pitch circle, turning in the same direction.
How to true a balance, repair a chipped dial, temper a spring or test a stone — the working bench-book of the American watch trade, arranged A to Z.
A gear wheel in which the teeth are on the inside of an annulus or ring, while its pinion works within its pitch circle, turning in the same direction.